DISSECT-N Post Market Data Collection Registry

Inclusion Criteria: * Subject is ≥18 years old * Subject was treated in the last 7 days, or is intended to be treated, with the Valiant Navion Thoracic Stent Graft System for a dissection in the thoracic aorta * Subject is willing to comply with standard of care clinical follow-up * Subject or legal representative or consultee, as applicable has consented for study participation and signed the approved Informed Consent Exclusion Criteria: * Subject is participating in an investigational drug or device study which may bias or interfere with the endpoints and follow-up of this study. * Subject is pregnant (not an exclusion if allowed per local regulatory requirements, pregnancy test to be performed where required) * Subject has an active COVID-19 infection or relevant history of COVID-19. Relevant history of COVID-19 is defined as availability of a positive COVID-19 test with sequela or hospitalization for treatment of COVID-19. Subjects with a positive COVID-19 test who were asymptomatic or had mild symptoms should be excluded only if the positive test was less than 3 months prior to enrollment.